This section introduces aspects that may be helpful to facilitate a better understanding of the inventions. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art. Any techniques or schemes described herein as existing or possible are presented as background for the present invention, but no admission is made thereby that these techniques and schemes were heretofore commercialized, or known to others besides the inventors.
Optical communications systems sometimes include components to monitor the status of optical paths within a network of paths to detect, e.g. a path interruption that may impact systems operation. Sometimes such monitoring is performed by use of an optical supervisory channel (OSC) detected at a receiver node of the system, and may additionally transmit system-related data via modulation of the OSC.